On a car stereo what does CrO2 big C little r big O But little 2.... please help

Question

On a car stereo what does CrO2 big C little r big O But little 2.... please help

Answer 1

It is a type of tape used in cassettes to lower tape hiss.  Push the button and you will hear a difference vs. having it turned off.

Chromium Oxide.

Answer 2

must be a cassette tape player.

chrome oxide was a type of tape that had a higher bias during the recording process.

it made the reproduction slightly brighter.

most pre recorded tapes were not high bias.  blank tapes, the higher priced ones, were